叠式曝气生物滤池预处理高氨氮原水

D-UBAF for Pretreatment of High Ammonia Nitrogen Raw Water

针对南方地区存在季节性高氨氮和有机物污染的水源水,采用叠式曝气生物滤池进行生物预处理。枯水期水温≥5℃,滤速为8m/h,气水比为0.5～1.5,原水氨氮、CODMn和浊度的周均值分别为5.02～9.45mg/L、5.79～10.1mg/L和19.7～63.1NTU,叠式滤池出水对应指标分别为0.30～0.96mg/L、3.24～5.85mg/L和3.83～19.9NTU(去除率分别为90.3%、42.7%和66.3%),符合《地表水环境质量标准》(GB3838—2002)的Ⅲ类标准。丰水期滤速为12m/h,气水比为0.3～0.5,原水氨氮、CODMn和浊度的周均值分别为2.19～3.41mg/L、5.30～7.56mg/L和27.3～40.1NTU,叠式滤池出水对应指标分别为0.18～0.41mg/L、2.87～4.50mg/L和5.43～16.8NTU(去除率平均为89.3%、40.2%和65.0%),符合GB3838—2002的Ⅱ类标准。初滤池去除了原水中大部分可滤SS,为曝气生物滤池的稳定运行创造了条件,同时使曝气生物滤池过滤水头损失的24h变化量不超过2kPa,满足了多座滤池共用鼓风曝气系统,实现均匀曝气对过滤水头损失的控制要求。叠式曝气生物滤池的工艺投资约为140～180元/m3,运行费用约为0.05～0.07元/m3。

According to the seasonal high ammonia nitrogen and organic pollution in raw water in subtropics, D-UBAF was used for its pretreatment. In low flow period, the temperature of raw water is above 5 ℃, filtration rate is 8 m/h, and gas-water ratio is 0.5 to 1.5. When the weekly average concentrations of NH3 - N, CODMn and turbidity of raw water are 5.02 to 9.45 mg/L, 5.79 to 10.1 mg/L and 19.7 to 63.1 NTU, the corresponding indexes of the treated water from D-UBAF are 0.30 to 0.96 mg/L, 3.24 to 5.85 mg/L and 3.83 to 19.9 NTU, and the removal rates are 90.3% , 42.7% and 66.3% respectively, which meet the Ⅲ criteria specified in Environmental Quality Standards for Surface Water （GB 3838 -2002）. In high flow period, the operating parameters are filtration rate of 12 m/h and gas- water ratio of 0.3 to 0.5. When the weekly average concentrations of NH3 - N, CODM, and turbidity of raw water are 2.19 to 3.41 mg/L, 5.30 to 7.56 mg/L and 27.3 to 40.1 NTU, the corresponding indexes of the treated water from D-UBAF are 0.18 to 0.41 mg/L, 2.87 to 4.50 mg/L and 5.43 to 16.8 NTU, and the removal rates are 89.3%, 40.2% and 65.0% respectively, which meet the Ⅱ criteria specified in Environmental Quality Standards for Surface Water （GB 3838 -2002）. In the DBAF of the D-UBAF system, the majority of filterable suspended solids in raw water can be removed, which can cre- ate the essential condition for the UBAF stable operation, and the variable quantity of filtering head of UBAF is no more than 2 kPa after filtration for 24 h. It also meets the requirement of head loss control for even aeration by multiple D-UBAFs who share a diffused aeration system. The process investment of D- UBAF is about 140 to 180 yuan/m^3 and the operation cost is about 0.05 to 0.07 yuan/m^3.